This invention relates to a cam arrangement for knitting machines, especially circular knitting machines with a first support in the form of a cam support, at least one second support in the form of a segment, at least one cam part mounted on the segment and at least one fixing device for interchangeable fixing of the one support on the other support, wherein the fixing device comprises a first claw associated with the first support and a tightening means including a coupling pin associated with the second support.
The segments of a knitting machine cam are as a rule fixed to the lock or cam support of the knitting machine with screws. Such an arrangement has the disadvantage that the exchange of the segments is very time consuming, because the screws must each be screwed through a number of rotations completely out of at least the lock or cam support.
It has therefore already been proposed to fix the segments on the lock support with the aid of quick connectors. In this respect a known lock arrangement of the kind initially referred to (DE-PS 1 938 891) has a coupling pin adapted to fit in a bore of the segment and having at one end a head bearing on the segment and at the other end a wedge surface. The lock support is provided with a claw-like recess, which has a clamping surface cooperating with the wedge surface. In the aligned state of the segment the two surfaces are opposed with a space therebetween. The fixing of the segment to the lock support is effected in simple manner in that the coupling pin of the segment is turned through about 180.degree. and the wedge surface is thereby applied to the clamping surface, until a firm press fit is produced.
Such a quick connector had many advantages, because only half a turn of the coupling pin is necessary for fixing the segment to the lock body. Practical investigations in circular knitting machines have shown however that the known quick connector is largely unusable. Only small departures from tolerance lead to ineffective clamping or tightening and the unavoidable vibrations of a knitting machine in operation can lead to loosening of the clamping connection. Moreover the clamping forces do not act axially but outside the axis of the coupling pin, which can lead to poor clamping and also to canting of the coupled parts.